Search results
Results from the WOW.Com Content Network
Some species, including woodpeckers, have two egg teeth; one on both the upper and lower bill. [4] After time the egg tooth falls off or is absorbed into the growing chick's bill. [5] Some precocial species such as the kiwi, and superprecocial species including megapodes, do not require an egg tooth to assist them in hatching. They are strong ...
Altricial birds are less able to contribute nutrients in the pre-natal stage; their eggs are smaller and their young are still in need of much attention and protection from predators. This may be related to r/K selection; however, this association fails in some cases. [18] In birds, altricial young usually grow faster than precocial young.
Because of this, birds usually have a smaller number of bones than other terrestrial vertebrates. Birds also lack teeth or even a true jaw and instead have a beak, which is far more lightweight. The beaks of many baby birds have a projection called an egg tooth, which facilitates their exit from the amniotic egg. It falls off once the egg has ...
Female birds are able to produce more of a certain gender of birds that are more likely to survive under extreme conditions. In birds, the females' egg determines the gender of the offspring, not the male's sperm. In zebra finches, a study showed the effect of food on gender ratio production. For females, egg production is a metabolically ...
In hoatzins, some birds (mostly males) help their parents incubate later broods. The incubation period, the time from the start of uninterrupted incubation to the emergence of the young, varies from 11 days (some small passerines and the black-billed and yellow-billed cuckoos ) to 85 days (the wandering albatross and the brown kiwi ).
Typically, after courtship, the male fertilises the eggs and then collects them in his mouth, holding onto them until they hatch. During this time he cannot feed. During this time he cannot feed. Among the maternal mouthbrooding cichlids, it is quite common (e.g., among the mbuna) for the male to fertilise the eggs only once they are in the ...
Doctors are urging all parents to hold on to their kid's baby teeth after the tooth fairy comes to visit -- and not for sentimental reasons. According to a recent study, baby teeth contain an ...
Granivorous (seed-eating) birds, for example, have ridges in their tomia, which help the bird to slice through a seed's outer hull. [20] Most falcons have a sharp projection along the upper mandible, with a corresponding notch on the lower mandible. They use this "tooth" to sever their prey's vertebrae fatally or to rip insects apart.